Hyaluronic acid or glycerine: which is the best humectant ?
There's a widespread misconception that hyaluronic acid is the best humectant, and that products containing it are essential for well-moisturized skin. The marketing surrounding this ingredient is such that it seems logical to believe it. However, the science is very different. Here's why glycerine is often preferable, and how to read an INCI list to choose a good moisturizing product.
Maintaining confusion around hyaluronic acid.
The cosmetics industry plays on the confusion between two very different things: the injections of hyaluronic acid, performed by a physician in the dermis, and the’local application of hyaluronic acid in a cream or serum. This confusion leads us to believe that the anti-aging effects of cosmetic application are spectacular, which is inaccurate: a surface-applied humectant does not have the same mechanism as an injected filler.
However, products containing hyaluronic acid are not bad (except for allergies). The point is not to demonize them, but to put a bit of science back into the equation: there are other humectants that are at least as interesting, and sometimes even more so.
The 500-dalton rule and molecular weight.
Humectants are molecules that attract water and moisturize the skin. Their molecular weight counts for a lot: in cosmetics, the «500-dalton rule» is that above a weight of 500, a molecule has great difficulty penetrating the skin barrier. This is not an absolute law (other criteria come into play), but a good benchmark.
Glycerin (92) is well below the threshold, moisturizing the deep layers of the epidermis. Hyaluronic acid, on the other hand, weighs between 20,000 and 2 million daltons: it acts above all to on the surface, by forming a film that retains water without penetrating deeply. That's the difference.
Very low molecular weight hyaluronic acids (below around 50,000 daltons) are sometimes described in the literature as potentially pro-inflammatory. This point is the subject of scientific debate and suggests that hyaluronic acid should not be seen as a universally superior active ingredient.
The conclusion is not to avoid hyaluronic acid, but to avoid being influenced by marketing: knowing how to decipher the INCI list allows you to choose products that really correspond to your skin. Glycerine, often at the top of the list, is an excellent first signal.
Our moisturizing serums with hyaluronic acid.
Let's start with a reminder: a good hyaluronic acid serum remains an excellent surface moisturizer, forming a water-retaining film and temporarily smoothing skin texture. Here are three well-formulated hyaluronic acid moisturizing serums, deciphered with BeautyDecoded scores - often combined, incidentally, with glycerine and niacinamide.
Vichy Minéral 89 Probiotic Fractions - fortifying moisturizing serum
A moisturizing serum that combines hyaluronic acid with niacinamide, glycerin and probiotic fractions to rebalance and strengthen the skin barrier. A light texture that moisturizes and soothes, with the signature of a thermal spring water. Dry skin score of 91 and neutral sensitive skin score (0) high hydration and excellent tolerance. Its formula relies on the synergy of HA + glycerine + niacinamide rather than hyaluronic acid alone.
AH combined with glycerin, niacinamide and probiotics, reinforces the barrier, light texture, good tolerance.
May lack richness on very dehydrated skin; seal with a cream.
A relevant option as a hyaluronic acid moisturizing serum: the formula combines HA, glycerin, niacinamide and probiotics to rebalance the barrier, with excellent tolerance. Users adopt it over time; some with very dehydrated skin use it in conjunction with a richer cream.
«Good moisturizer with probiotics and niacinamide to rebalance the barrier, I couldn't do without it.»
«Moisturizes well and reduces redness, I've already repurchased it twice.»
«Good but not moisturizing enough for my very dehydrated skin.»
Avene Hyaluron Activ B3 Serum - AH + niacinamide dermatological serum
A highly purified dermatological moisturizing serum: hyaluronic acid, niacinamide, glycerin and adenosine, on a soothing base. A short, well-tolerated formula from a brand for sensitive skin. Dry skin score of 91 and neutral sensitive skin score (0) High hydration and excellent tolerance. Its good redness score (83.3) reflects the soothing effect of niacinamide.
Short, well-tolerated formula, AH combined with niacinamide and glycerin, plumping effect on damp skin.
Moisturizing rather than corrective; price considered a little high by some.
A relevant option as a hyaluronic acid moisturizing serum for sensitive skin: the short formula combines AH, niacinamide and glycerin, and is well tolerated. Users praise the moisturizing and plumping effect on damp skin, while reminding us that this is first and foremost a moisturizer, not a corrective anti-aging product.
«Superb texture and penetration, hydration on target, a must-have.»
«Very pleasant and plumping applied to damp skin; a moisturizing serum that complements the routine well.»
«Good hydration but expensive for effects that remain correct without more.»
SVR Ampoule Hydra Vitamine B3 - the triple serum hyaluronic acid + niacinamide
A popular moisturizing serum that combines three forms of hyaluronic acid (including one crosspolymer and one hydrolyzed, of different molecular weights) with 5 % niacinamide and glycerin. A multi-molecular-weight architecture designed to hydrate on several levels. Dry skin score of 77 and sensitive skin score of -0.5, virtually neutral Good hydration and tolerance. Its good redness score (81.6) reflects the soothing effect of niacinamide.
Three multi-molecular-weight hyaluronic acids, niacinamide 5 %, plumping effect, excellent value for money.
Texture sometimes considered thick or slightly sticky; seal with a cream.
A relevant and highly-rated option as a hyaluronic acid moisturizing serum: three forms of HA and 5 % niacinamide make this a complete and accessible formula. Users praise its plumping, moisturizing effect, although some note that the texture is a little thick or sticky, and should be measured out according to skin type.
«Super serum that moisturizes dry skin, slight downside: a little sticky.»
«Plumping effect and protection against pigmentation spots, I really like it.»
«Perfect in the evening before the nourishing cream and retinol.»
Three moisturizing products hyaluronic acid-free.
Conversely, here are three equally effective moisturizing products, but without hyaluronic acid, relying on glycerin and other humectants, deciphered with BeautyDecoded algorithmic scores and user feedback.
Missha Time Revolution The First Treatment Essence - ferment lotion
A hyaluronic-acid-free lotion-essence that relies on fermented ingredients rich in humectants, niacinamide and sodium PCA (an NMF). A moisturizing first step that prepares the skin for the rest of the routine. Neutral sensitive skin score (0) Very good tolerance. Its fluid texture is suitable for all skin types, as a light moisturizing layer before cream.
Hyaluronic acid-free, humectant ferments and NMF, niacinamide, good tolerance, all skin types.
Light moisturizing to be complemented by a cream; product mostly available online.
A relevant option as a first moisturizing step without hyaluronic acid: ferments and sodium PCA provide light hydration, and niacinamide supports the barrier. Use before cream to prepare skin. Please note, only one evaluation available.
«First step in my evening routine, it helps the rest penetrate, I repurchase.»
Bioderma Hydrabio Gel-Cream - Glycerin + squalane gel-cream
A hyaluronic-acid-free gel-cream formulated around the glycerin (in 2ᵉ INCI position), squalane and niacinamide. A light texture that moisturizes without weighing down, perfect for normal to combination skin. Sensitive skin score of -0.75, virtually neutral. Its lightness makes it ideal for normal to oily skin; on dry skin, a richer formula is required.
Hyaluronic acid, glycerin and squalane-free, light texture, gentle price, airless tube.
Not suitable for dry skin; packaging sometimes difficult to empty.
A relevant option as a moisturizing gel-cream without hyaluronic acid: glycerin, a small molecule, moisturizes effectively, and squalane reinforces the lipidic film. Users praise its light, fast-absorbing texture, noting that it may lack richness on dry skin.
«Very good all-day hydration, no unpleasant fragrance, airless tube.»
«For the past three years in the evening as a complement to a suitable routine, it moisturizes really well.»
«Light, pleasant gel that penetrates easily but doesn't moisturize my dry skin enough.»
La Roche-Posay Toleriane Sensitive Riche - Ceramide cream
A hyaluronic-acid-free moisturizing cream rich in glycerine, ceramides and squalane. fragrance-free. Designed for normal to dry sensitive skin, especially in winter. Dry skin score of 84 and neutral sensitive skin score (0): a comforting, well-tolerated cream. Ceramides fill in intercellular cement to limit water loss.
Hyaluronic acid- and fragrance-free, with glycerin and ceramides, soothing, ideal for dry skin in winter.
Too rich for combination to oily skin.
A relevant option as a hyaluronic-acid-free moisturizer for normal to dry and sensitive skin: glycerin and ceramides comfort the barrier, fragrance-free. Users find it ideal at the end of their winter evening routine; on combination skin, it can be too rich.
«Ideal at the end of an evening routine in winter, penetrates well, skin is no longer tight.»
«For 2 years: normal to dry skin in winter, this cream is ideal.»
«For my combination skin, too rich and makes it shiny; useful in case of transient irritation.»
And for dry skin in winter ?
Beyond this selection, in winter, dry skin will appreciate lotions rich in glycerine combined with plant oils and green tea extracts, which provide comfort and antioxidants. The principle remains the same: good hydration doesn't depend on the presence of hyaluronic acid, but on the right combination of ingredients. balance between humectants (which attract water), emollients (smoothing) and occlusive agents (which retain water).
How to choose a moisturizing product.
To identify a good moisturizing product, follow a few simple steps:
Search for glycerin at the top of the INCI list one of the best humectants, small and penetrating.
Don't focus on the mention alone «hyaluronic acid» Its presence is neither a guarantee of quality, nor is it essential.
Aim for a complete formula humectants (glycerine, urea, panthenol, NMF), emollients (squalane, ceramides) and fats to retain water.
Adapting the richness of the texture skin type: gel-cream for oily skin, rich cream for dry skin.
Decipher your humectants with BeautyDecoded application.
BeautyDecoded is a mobile application for cosmetic analysis using artificial intelligence. It deciphers INCI formulations and generates compatibility scores for 80 skin types and profiles. It's not a medical consultation, but rather an objective way of choosing a moisturizing product according to a precise skin profile, without being influenced by the marketing of a single ingredient.
Discover the applicationYour questions about humectants.
Is hyaluronic acid really useless?
Why is glycerine often preferable?
What is the 500-dalton rule?
How do you know if a product is a good moisturizer?
What is the BeautyDecoded application?
Information for educational purposes only. It does not replace a medical consultation. Molecular weights and the «500-dalton rule» are guidelines for skin penetration, not absolute laws; the potentially pro-inflammatory nature of very low molecular weight hyaluronic acids is the subject of scientific debate. BeautyDecoded algorithmic scores do not prejudge individual tolerance: a test on a small area is recommended, and in the event of a known allergy to an ingredient, seek the advice of a healthcare professional. Several products on this page have a limited number of reviews: when this is the case, it is indicated on the product sheet, and the corresponding returns are indicative. The reviews displayed come from BeautyDecoders and have not been verified. No commercial partnership links this page to the marquess mentioned. © BeautyDecoded - Independent information. Dr Sylvain David, Plastic and aesthetic surgeon - Founder of BeautyDecoded.